Hey Madder, the chances of a ballistic object landing in that configuration, parallel with anything and just a foot away from a wall,... and not deforming it's shape are quite frankly near zero.
If the object fell in that part of the roof, it probably rolled about until it hit the wall. That would account for its position.
As for deformation, it depends on where it came from and how sturdy it is. For example, in the Air Photo Service pics one can see a large dark gray metal box that was ejected from Unit #3 and was lying on the ground, some 30 meters southwest of the building --- apparently intact.